hide_events_filter_values

add_filter( 'tribe_events_filter_values',  'demo_events_filter_values' );
 
function demo_events_filter_values( $values ) {
 
    foreach ( $values as $key => $value ) {
 
        if ( isset( $value['data']['slug'] ) ) {
 
            if ( '0' == $value['data']['slug'] ) {
                unset( $values[ $key ] );
                $values = array_values( $values );
            }
        }
    }
 
    return $values;
}
 
add_action( 'wp_footer', 'demo_wp_footer' );
 
function demo_wp_footer() {
?>
    <script>jQuery( 'select[name="tribe_eventcategory"]' ).removeAttr( 'disabled' );</script>
<?php
}